Of all the equipment you can use to refine the sound of your electric guitar, compression and sustain effects pedals are among the most common—and for a good reason. These pedals allow you to easily tame a note that would otherwise be a bit too strong, or to bring up the tail end of a sustained chord for maximum effect. In technical terms, your compressor's job is to shrink (or "compress") the dynamic range of the audio signal. The practical outcome is that loud sounds get quieter and quiet sounds get louder. A common use for the compression and sustain effects pedal is to stabilize volume and soften the "attack" of a note by curbing its onset and boosting its sustain. Adjusted to extreme settings, a compressor is also useful as a limiter. The low-end compression of these pedals is ideal for boosting notes as they fade, giving you a sustain effect that can add impact to the last note of a solo or enhance the effect of a rhythm riff. Restraining the louder end and amplifying the lower end, these pedals can actually boost and trim the guitar's volume simultaneously, reining in extremes to help balance the sound. Compared to other effects pedals, the role of the compression and sustain stompbox is subtle but invaluable. While some pedals are predisposed to complement certain styles of music or be used in highly specialized roles, the compressor is a fundamental link in any guitarist's chain, widely used no matter the song or genre.